docs: def rm(filename, serial=None):
      """
      Removes a referenced file on the micro:bit.
  
      If no serial object is supplied, microfs will attempt to detect the
      connection itself.
  
      Returns True for success or raises an IOError if there's a problem.
      """
      commands = [
          "import os",
          "os.remove('{}')".format(filename),
      ]
      out, err = execute(commands, serial)
      if err:
          raise IOError(clean_error(err))
      return True